Ballast tamper



C. JACKSON BALLAST TAMPER Filed Jan. 16, 1933 Patented Apr. 21, 1936 UNITED STATES PATENT OFFICE 7 Claims.

'Ihe subject matter of the present case is a continuation in part of my copending application, Serial No. 476,606, filed August 20, 1930, for Tampers and like impact tools.

The main objects of this invention are:

First, to provide an improved ballast tamper for railway ties and the like, which delivers a series of weighted uniform thrusts or pushes to thehballast and thereby efficiently packs the same witlout damage or crushing.

Second, to provide a device of this character, which is highly enicient and convenient to use and enables the performance of a large amount of work by an operator with comparatively little effort.

Third, to provide a tamper possessing the above desirable features, which is simple and economical in its parts and highly effective in operation.

Objects relating to details and economies of my invention will appear from the description to follow. The invention is defined and pointed out in the claims.

A structure which is a preferred embodiment of my invention is illustrated in the accompanying drawing, in which:

Fig. 1 is a view mainly in side elevation of a tamper embodying the features of my invention in operation, portions being broken away and shown in vertical section.

Fig. 2 is an enlarged fragmentary view partially in section on a line corresponding to line 2--2 of Fig. 1.

Fig. 3 is a fragmentary detail showing how the cam follower remains constantly in Contact with the cam during the operation of the device.

I have illustrated my improvements in the accompanying drawing as adapted by me for railway tie ballast tampers, although the structure illustrated, with proper modification in the tool, is adapted for use in other relations.

In the embodiment illustrated by the drawing, I provide a casing-like body or housing I having an electric motor housed therein, the rotor 2 of the motor being provided with a shaft 3 supported by bearings 4, 5 and 6. Between the bearings 4 and 5, the shaft is provided with an oval cam 1.

The cylindrical tool holder socket 8 is preferably formed integrally with a part of the housing and is shouldered at 9.

Within the socket, I arrange a bushing II) for the cam follower Il. This cam follower is provided with a head I2. The cam follower is supported in the bushing both for reciprocating andv (Cl. loll-14) rotative movement. At its outer end, the socket 8 is provided with laterally projecting ears I3.

The inner end of the cam follower is provided with a substantially flat right face so that the rotation of the cam follower does not affect the 5 relation of the face to the cam, but allows the cam follower to rotate to distribute the wear on the face. By the term righ I mean at right angles to the longitudinal axis of the cam follower.

I have found in practice that the cam follower does rotate so that the wear caused by the cam on the face is slight and is very uniformly distributed. In the present embodiment, the inward movement of the cam follower is controlled 15' solely by the oval cam.

The tool I4 is supported in operative relation to the cam follower by means of the holder I5, the inner end of which is engaged in the tool holder socket thereby holding the same in proper alignment. The tool and tool holder have non-circular portions which prevent rotative movement of the tool in the holder.

The tool is provided with an annular enlargement I6 reciprocating within the enlargement II 25 in the tool holder, the shoulder I8 at the outer end of the enlargement I'I serving as a stop. In operatio-n, when the tamping tool is allowed to rest on the ballast, as I9, for instance, the weight of the housing and motor causes the cam, cam follower, and tool to engage each other and remain in contact continuously during the operation of the device. The cam imparts a series of uniform pushes to the cam follower, which are transmitted by the tool to the ballast.

The housing is provided with a handle 20. To relieve shock when the tool is lifted or when it enters an opening or is otherwise in support, the tool holder is yieldingly mounted, it being provided with ears 2| disposed oppositely of the ears I3 on the tool holder socket. Bolts 22 arranged through these ears carry the springs 23 arranged between the ears I3 and the nuts 24 on the upper ends of the bolts which constitute thrust members. 45

I preferably provide means for automatically lubricating the cam and the cam follower, this means consisting of a lubricant reservoir 25 and the wick 25 which is folded upon itself to depend from the central holder 21 into ther path of the 50 cam so that as the cam rotates, its nose comes into contact with the wick and lubricant is therefore applied to the cam and delivered to the face of the cam follower. The result is that these parts are efficiently lubricated without excessive 55 use of lubricant and without the necessity of providing tight joints such as would be required if the cam rotated in a lubricant holding chamber.

In use, the tool rests upon the work or material to be tamped and supports the weight of the housing and motor through the cam and cam follower, the handle being provided for moving the device from place to place and for manipulating the tool on the work and for holding the machine in upright position. In the commercial structure, the housing and motor weigh approximately '70 pounds so that the machine operates to cause the tamping tool to deliver a series of uniform thrusts or pushes to the ballast. Each thrust push is backed up by the weight of the apparatus so that While the thrusts are smooth and uniform, they are nevertheless powerful and act to pack the ballast without breaking or crushing it.

In prior pneumatic and impact tampers, the tool delivered a series of hammer-like blows which tended to crush and otherwise damage the ballast. The present invention has been designed with the development of the art in mind and with the object in View of overcoming defects which such prior apparatus has developed.

In the present machine, I, in effect, support the motor and housing upon the upper end of the tamping tool which is substantially immovable by means of the cam follower and cam carried by the housing whereby the casing and its connected parts are lifted at each revolution of the cam, thus imparting a series of thrusts or pulsa- 1 tions to the tamping tool, each thrust or pulsation being equal to the weight of the housing and the parts connected thereto. The relation of the cam andcam follower is such that the cam follower is in contact with the cam at all times during the operation of the device. For this purpose, the cam and cam follower are hardened and are thoroughly lubricated.

The dimensions of the cam are preferably such that the same provide for a rise or lift of the motor and housing at each revolution, this resulting in a thrust or downward pulsation equal to the weight of the motor and housing upon the tamping tool. In the construction illustrated, the weight of the motor and housing is supported upon the cam shaft at all times through the cam follower and the tamping tool. To make sure that the cam follower remains in constant contact with the cam, I provide a clearance between the annular head I 2 of the tappet and the shoulder at the lower end of the tappet bushing l0.

Fig. 1 illustrates the tamper in operation in packing the ballast I9 under one of the railway ties 28. The oval cam coacts with the flat right face at the upper end of the cam follower to produce a series of uniform pushes, the entire weight of the housing and parts carried thereby being applied to the tool through the cam and cam follower. The force of each thrust is substantially equal to the weight of the housing and its connected parts, which, as pointed out above in the commercial structure, is about 70 pounds. The face of the cam follower remains in contact with the cam substantially at all times and the result is a series of heavy thrusts by the tool, instead of a series of blows, which acts to pack the ballast without damage, such as crushing or breaking.

The present invention represents a radical departure from the prior art, inasmuch as the tamping tool is caused to deliver a series of substantially uniform weighted pushes or thrusts which effectively pack the ballast without crushing the same. pneumatic tools, the sharp hammer-like blows delivered by the tool caused the latter to break and crush the ballast. This destroyed the drainage properties of the ballast and resulted in the rotting of the ties. This undesirable feature of prior structures is entirely eliminated by my present invention.

I have illustrated and described my improvements in an embodiment which I have found very practical. I have not attempted to illustrate or describe other embodiments or adaptations, as it is believed this disclosure will enable those skilled in the art to embody or adapt my improvements as may be desired.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. A ballast tamper comprising in combination a housing, a cam shaft `iournaled thereto, a cam on said shaft, a cam follower in said housing, and a ballast tamping tool associated with said housing for coaction with said cam follower, whereby in operation, the weight of the housing is transmitted through the cam shaft to the cam follower and ballast tamping tool, the speed of the motor being such that the cam follower is caused to remain substantially at all times in contact with the cam, so that the ballast tamping tool delivers a series of weighted uniform thrusts to the ballast, the cam, cam follower and tool remaining in continuous contact for all motor speeds up to the maximum operative yspeed thereof.

2. A tamper comprising in combination a housing, a motor carried by said housing and having a shaft, an oval cam on said shaft, a cam follower in said housing, and a tamping tool associated with said housing for coaction with said cam follower, whereby in operation, the weight of the motor and housing is transmitted through the cam to the cam follower and tamping tool, causing the cam follower to remain substantially at all times in contact with the cam, so that the tamping tool delivers a series of uniform thrusts or pulsations to the material to be tamped, the cam, cam follower and tool remaining in continuous contact for all motor speeds up to the maximum operative speed thereof.

3. A tamper comprising in combination a housing, a motor carried by said housing and having a substantially Ahorizontal shaft, a cam on said shaft, a substantially vertical cam follower in said housing, and a substantially vertical tamping tool carried by said housing, whereby in operation the weight of the housing and motor is transmitted to the ballast through the shaft, cam, cam follower and tool, the speed of the motor being such that the cam follower is caused to remain substantially constantly in contact with the cam so that the tool delivers a series of weighted uniform thrusts to the material to be tamped, the cam, cam follower and tool remaining in continuous Contact for all motor speeds up to the maximum operative speed thereof.

4. A tamper comprising in combination a substantially vertical tamping tool for resting on the material to be tamped, a substantially vertical cam follower adapted to rest on said tamping tool in operation, an oval cam for resting on said cam follower in substantially constant contact therewith in operation, and a cam driv- As pointed out above, in prior ing motor and housing supported by said cam, whereby the tool delivers a series of uniform pushes to the material and packs the same by virtue of the speed of said motor, the weight of the parts, the shape of said cam and the substantially constant contact between the cam, cam follower and tool, the cam, cam follower and tool remaining in continuous contact for all motor speeds up to the maximum operative speed thereof.

5. A ballast tamper comprising in combination a motor having a substantially horizontal shaft, a cam on said shaft, a substantially Vertical cam follower, Aand a substantially Vertical tamping tool, whereby in operation the weight of the motor is transmitted to the ballast through the shaft, cam, cam follower and tool, the speed of the motor being such that the cam follower is caused to remain substantially constantly in contact with the cam so that the operation of the cam causes the tool to deliver a series of thrusts to the ballast, the cam, cam follower and tool remaining in continuous contact for all motor speeds up to the maximum operative speed thereof.

6. A tamper comprising in combination a substantially vertical tamping tool for resting on the material to be tamped, a substantially vertical cam follower adapted to rest on said tamping tool in operation, a cam for resting on said cam follower in substantially constant contact therewith in operation, and a cam driving motor supported by said cam, the speed and shape of said 'cam being such that the tool delivers a series of uniform pushes to the material and packs the same, the cam, cam follower and tool remaining in continuous Contact for all motor speeds up to the maximum operative speed thereof.

7. A tamper comprising in combination a substantially vertical cam follower, a cam for resting on said cam follower in substantially constant contact therewith in operation, and a weighted body supported by said cam, the speed and shape of said cam being such that the cam delivers a series of pushes to the cam follower, the cam and cam follower remaining in continuous Contact for all motor speeds up to the maximum operative speed thereof.

CORW'ILL JACKSON. 

